Whip stock locking and releasing apparatus



Feb. 11, 1958 R. P. HANNA 2,823,012

WHIP STOCK LOCKING AND RELEASING APPARATUS Filed Feb. 6, 1956 2Sheets-Sheet l 22 I I I 23 v 26$ '25 l4 FIG. 1

4 Fne. 3 uvmvron aosesz'r P. HANNA ATTORNEYS Feb; 11, 1958 R. P. HANNA2,323,012

WHIP STOCK LOCKING AND RELEASING APPARATUS Filed Feb. 6, 1956 2Sheets-Sheet 2 A ww M W. a .5 up. nmufinw ...1\3 v m V? A INVENTOR'ROBERT P. HANNA avmzmpmst w I Armwm FIG. 4

United States Patent WHIP STOCK LOCKING AND RELEASING APPARATUS RobertP. Hanna, Oakview, Calif., assignor, by mesne assignments, of forty-ninepercent to C. J. Wilkinson, Bakersfield, Calif.

Application February 6, 1956, Serial No. 563,532

12 Claims. (Cl. 2551.6)

This invention relates generally to oil tools and more particularly to atool adapted to be inserted between a string of drill pipe and a drillbit for holding a whip stock in a desired position while it is beinglowered into an oil well bore hole.

In the lowering of conventional type whip stocks for the purpose ofdeflection drilling, there is often encountered difiiculty in properlypositioning the whip stock in the bottom of the bore hole in a desiredorientation. Normally, the collar portion of the whip stock is supportedby the end of the drill pipe string with one shear pin. After the whipstock is in position at the bottom or at an intermediate location in thebore hole, the pin is intentionally broken or sheared when the drillingcommences. After the shear pin is broken, movement of the drill pipestring through the collar portion of the whip stock can often move thewhip stock from its desired orientation, although once the drill pipestring has passed through and wedged the Whip stock into tightengagement with the side walls of the bore hole, the whip stock willremain in its set position.

Another difficulty in lowering conventional whip stocks is theirtendency to arcuately swing about the shear pin as a pivot point. Thereis thus the possibility of the whip stock becoming caught in caveportions of the bore hole side walls or hung up by bridges and likeobstructions during the lowering process.

Bearing the above noted difliculties in mind, it is a primary object ofthe present invention to provide an improved means for holding aconventional type whip stock to a drill pipe string while itis beinglowered into a bore hole in a manner such that swinging movements andthe possibility of the whip stock becoming dislocated after once beingpositioned on the bore hole bottom are avoided.

More particularly, an object is to provide a whip stock locking andreleasing means which will hold the whip stock in a rigid position withrespect to the drill pipe string while it is being lowered into the borehole, and which will retain the whip stock in its initially setorientation during the first downward movements of the string throughthe whip stock collar portion, whereby once the whip stock is set in adesired position, it will remain substantially in such position.

Still another object of this invention is to provide a whip securedagainst rotation with respect to the drill pipe string when it is beinglowered in the bore hole.

There is also provided in one or more side walls of the pipe sectionsuitable lever elements pivoted adjacentthe flange portions and adaptedto swing laterally outwardly to engage mating shoulder portions withinthe corresponding channels. When the lower ends of the lever elementsare seated on the shoulder portions, the drill pipe string is lockedagainst longitudinal or axial downward movement through the collar. Anannular ring of suflicient diameter is provided on the lower portion ofthe pipe section adapt-v ed to engage the underside of the collarportion to prevent axial upward movement of the pipe section and pipestring with respect to the collar portion.

Thus, the interengaging flanges and channels prevent rotation andarcuate swinging of the whip stock relative to the drill pipe string,while the various lever elements in their laterally extending positionsin co-operation with the annular ring prevent relative longitudinal oraxial movement between the whip stock and the drill pipe string.

Within the pipe section there is provided a piston having a centralpassage for passing mud from the drill pipe string out through the drillbit. The piston is also provided with sloping side wall portionsadjacent suitable slot openings arranged to receive the upper ends ofthe pivoted lever elements. The levers are so designed that their upperends bear against the sloping side walls of the piston whereby downwardmovement of the piston cams these upper portions outwardly to retractthe lower ends of the lever elements and thus free them fromtheshoulders in the collar portion channels. A mud passage control stocksecuring means which may be operated from the surface of the bore holefor releasing the whip stock from the end of the drill pipe string onceit has been lowered into a desired position at the bottom of the borehole.

- These and other objects and advantages of this invention are attainedby providing a series of longitudinal channels in the inside collarportion of the whip stock. A pipe section having a series oflongitudinal flanges projecting from its side walls adapted to engagethe channels of the whip stock collar, is designed to be insertedbetween the drill pipe string and drilling bit. The whip stock is thusmeans is provided for enabling mud pressure above the piston in the pipesection to build up to a value suflicient to force the piston downwardlywhen it is desired to move the drill pipe string on through the whipstock collar for commencing an offshoot drilling operation. After thelever elements have been retracted, the entire drill pipe string islowered on through the collar. portion, but relative rotation or adisorientation of the whip stock is pre vented during the initialmovements of the drill pipe string as a result .of the flange members onthe pipe section side walls still engaging the longitudinal channels cutin the collar portion. By the time the flanges pass out below thechannels, the whip stock is sufficiently wedged into the formation toprevent any serious possibility of becoming angularly moved from itsdesired orientation.

A better understanding of the invention and its various features andadvantages will be had by referring to the accompanying drawings, inwhich:

Figure 1 is an elevational view of the whip stock locking and releasingapparatus of this invention shown secured to the end of a string ofdrill pipe in position at the bottom of a bore hole;

Figure 2 is an enlarged perspective cutaway view of a collar portion ofthe whip stock of Figure 1; I

Figure 3 is an enlarged side view partly. cut away of a portion of thewhip stock lockingand releasing ap paratus; I

Figure 4 is an enlarged cross sectional view of the locking andreleasingapparatus in locked position taken in the direction of the arrows 4-4 ofFigure 3; and,

Figure 5 is a view similar to Figure 4 showing the locking and releasingapparatus in released position.

Referring to Figure 1, there is illustrated an oil well bore hole 10within which is shown the lower end portion of a string of drill pipe 11coupled by a tool joint 12 to a pipe. section 13 constituting the whipstock locking and releasing apparatus of this invention. As shown, thepipe section 13 is surrounded at its lower end by the collar 14 3 of aconventional whip stock 15. The drilling bit is secured below the collar14 to the end of the locking and releasing pipe section 13, a portion ofthe bit being visible in Figure 1.

Refern'ngnow to Figure 2, the collar portion 14 of the whip stock isshown in greater detail. In accordance with a feature of the invention,the inside collar portion 16 is provided with a series of longitudinallycut channels 17, 18 and 19. This inside portion 16 may comprise aninsert which may be'secured within the conventional whip stock collar14, or the whip stock may be initially provided with a suflicientlythick collar to enable the desired channels to be cut therein. Each ofthe channels 17, 18 and 19 are circumferentially spaced 120 and areprovided substantially midway of their length, with a shoulder 20, theremaining portions of the channels below the shoulders being shallower,but still having side wall portions 21.

Referring to Figure 3, the side wall portions 21 of each of the channelsare adapted to receive flange means in the form of two parallel flangeprojections 22 and 23 secured in a longitudinal direction to the pipesection 13. The two flanges 22 and 23 terminate in a solid block portion24 at their lower ends as also clearly shown in Figure 3. The distancebetween the channels 22 and 23 is dimensioned such that the outsidewalls of the flanges will engage the inside wall portions 21 of thechannel in a closely fitting relationship whereby the pipe section 13 islocked against relative rotation with respect to the collar portion 14when the flanges are engaged within the respective channels. Thechannels 18 and 19 are similarly adapted to receive corresponding flangemeans running longitudinally along the side walls of the pipe section 13(not shown). Since the construction of the flanges and channels areidentical for all three, description of one will 'suflice for all.

Referring again to Figure 3, there is provided a lever element 25pivoted for swinging movement in a vertical plane as by a pivot pin 26extending between the flanges 22 and 23. The upper end of the leverelement 25 is adapted to be received in a slot opening 27 in the pipesection 13, while the lower end of the lever element is adapted to seatagainst the shoulder of the corresponding channel within which theflanges 22 and 23 are disposed. This first position of the lever elementis best shown by reference to Figure 4 taken in the direction of thearrows 44 of Figure 3.

Referring to Figure 4, the pipesection 13 is shown secured at its upperend to the lower portion of the pipe string 11 by the tool joint 12.This joint is in the form of an adapter whereby the inside diameter ofthe pipe section 13 may be made somewhat larger than the inside diameterof the conventional drill pipe 11. As shown, the upper portion of thepipe section 13 includes an inner cylindrical chamber 28 within whichthere is mounted for reciprocal up and down movement a piston member 29elongated in form and provided with sloping or tapered side wallsurfaces 30. The sloping surface is juxtaposed the slot opening 27through which the upper-end of the lever element 25 projects. The upperend of the piston member 29 includes a piston head 31 provided withsuitable sealing rings for engagement with the sides of the cylindricalchamber portion 28, and a reduced diameter portion below the piston head31 leaving an annular recess 32 within which is disposed a compressionspring 33. The upper end of the spring 33 engages the underside portionsof the head 31 while the lower end seats on an annular ledge projectingradially inwardly from'the side wall of the pipe section 13 as shown.The compression spring thus biases the piston 29 in an upward directionuntil an enlarged diameter portion immediately above the sloping sidewalls engages the underside of the annular ledge projection. Thisenlarged diameter portion includes an annular groove 34 adapted toreceive an annular rib 35 when the piston 29 is moved to its downwardposition as shown in Figure 5, thereby providing a fluid tight seal toprevent mud from passing through the slot opening 27 to regions abovethe piston member.

Similarly, at the lower end of the piston member 29 there is provided anenlarged diameter portion having an annular groove 36 adapted to engagea rib 37 projecting from the inner side walls of the pipe section 13,when the piston is in its downward position. There is also provided alatch 38 receivable in a detent 39 in the lower body portion of thepiston member to hold the piston member in its downward position againstthe compression of the spring 33, as also clearly shown by reference toFigure 5.

Below the latch means 33 the pipe section 13 includes an annular ringflange 40 of larger diameter than the inside diameter of the collar,portion 16 such that the lower end of the collar is engaged by the uppersurface of the :ring whereby the whip stock 15 is prevented from movingaxially off the end of the pipe section 13. Axial movement of the collarwith respect to the pipe section in the opposite or upward direction isprevented by the lower end of the lever element 25 bearing against theshoulder 20 of the channel 17.

Referring to the upper portion of the pipe section 13 there is provideda mud passage control means in the form of a ball check valve 41.limited in movement by a stem 42 having an enlarged head verticallymovable in a recessed space43 in the ball. The upper end of the stem-42connects to a spider support 44 secured rigidly to the inside walls ofthe pipe section 13. A springis arranged as shown to normally bias theball 41 against the upper opening of a conventional mud passage 45passing through the central portion of the piston 29. By thisarrangement, the downward movement of the ball 41'upon downward movementof the piston 29 is limited by the enlarged head portion of the stem 42engaging the upper end of the recessed space within the ball all asshown clearly in Figure 5. Thus, when the piston 29 is in its downwardposition, the mud passage 45 is opened to permit circulation of mudthrough this passage and out the end passage portion 46 on through thepipe section to the drill bit.

An import-ant constructional feature of the pipe section 13 resides inthe wall portion adjacent the flanges 22 and pivot point .26 of thelever element 25. As shown clearly in Figure 4, this wall is providedwith an undercut portion 47 which is adapted to engage a similarlycontoured portion on the lever element 25. By this arrangement,compression forces transmitted through the lever element 25 from theshoulder 20 are home by the undercut portion 47 rather than thepivot'pin 26, thereby relieving the pivot pin of this load. The wallportion immediately below the pivot pin 26 is also provided with acavity 48 retaining a leaf spring 49 normally biasing the lower end ofthe lever element 25 outwardly.

The operation of th apparatus will be evident from the abovedescription. In securing the whip stock to the end of the drill pipe,the pipe section 13 with the bit secured to one end thereof, is passedthrough the collar 14 of the whip stock so that its upper end is inposition to be engaged .by the last pipe in the drill pipe string shownas 11 inFigures 4 and 5. The piston member 29 is held in its upwardposition by the compressionspring 33. In this position, the biasingspring 49 urges the lever element 25 outwardly against the inside of thechannel'17 whereby the lower end thereof is seated on the shoulder 20.The relative position of the whip stock is noted with respect .to thedrill pipe string so that it may be properly oriented by rotating thedrill pipe string when the whip stock has reached the bottom of the borehole.

With the various components. of the pipe section 13 shown in'thepositionof Figure 4, it will be readily apparent that the drill pi estring 11 is lockedagainst relative rotation with respect to the collar14 in view of the side flanges 22 and 23 within the correspondingchannel 17 and the other flanges (not shown) in the other correspondingchannels 18 and 19. It will also be clear that relative axial movementof the whip stock and drill pipe string 11 is prevented by the variouslever elements such as the lever element 25, in engagement with theshoulders such as the shoulder 20, in the corresponding channels and bythe lower ring 40 resting against the bottom portion of the collar.

The collar 14 is of suflicient axial length that the whip stock is heldin rigid position against swinging motion while it is being lowered inthe bore hole. Thus, the possibility of the whip stock engaging bridgesor caves in the bore hole during the lowering process are substantiallyreduced.

When the whip stock reaches the bottom of the bore hole and is properlyoriented, the mud pressure is raised by the mud pump at the surface ofthe bore hole to increase the pressure within the cylindrical chamberportion 28 of the pipe section 13. This increase in pressure issufficient to initially move the piston member 29 in a downwarddirection. A large pressure is built up inasmuch as the mud passage 45is closed off by the ball 41; however, after initial motion of thepiston 29 overcoming the starting friction, not as much pressure isnecessary to maintain the piston 29 in its downward movement. Therefore,it is not necessary that the passage 45 continuously remain closed.However, to insure that sufiicient mud pressure is established tomaintain the piston in its downward movement, a control means in theform of a restricted orifice 46 may be provided in the lower end of themud passage. 7

As the piston member 29 moves downwardly, the sloping wall 30 will camthe upper end of the lever element 25 outwardly to swing the elementin acounter clockwise direction about the pivot pin 26 as viewed in Figures4 and 5, thereby retracting the lower end portion of the lever elementfrom the shoulder 20. The retracted or closed position of the leverelement 25 is clearly shown in Figure 5 with the piston member 29 in itsdownward position. The other lever elements spaced 120 about the pipesection are simultaneously retracted in the same manner.

It will be noted that in the downward position the various stopscomprising the grooves 34 and 36 and the mating annular ribs and 37 atthe upper and lower ends of the piston respectively, :are in tightengagement whereby mud is prevented from passing through the open slots,such as the slot 27, into the portions of the pipe section above andbelow the piston. It will also be noted by reference to Figure 5 that inthe downward position, the piston member 25 is retained and locked inposition by the latch 38 engaged within the detent 39 at the lower endof the piston. Further, the ball 41 is limited in downward movement bythe stem end 43, as shown, whereby the mud passage 45 is open forconventional circulation of mud.

With the various components of the apparatus in the position shown inFigure 5, the drill pipe string 11 may now be lowered thereby slidingthe pipe section 13 on through the collar 14 until the various sideflanges such as the flange 22 slide past the lower ends of the channelswhereby the pipe section 13 is then free to rotate independently of thecollar 14 and the drilling operation can commence.

It is thus seen that the locking against relative axial movement isfirst released by retraction of the various lever elements. A giveninterval of time thereafter depending upon the downward rate of movementof the drill pipe 11, the locking against relative rotation is released.By the time relative rotation can take place, the pipe section has moveddown sufliciently within the whip stock to thoroughly wedge the whipstock into the formation and thus lessen the possibilityofdisorientation of the whip stock during the initial axial movements ofthe drill pipestring.

The drilling can then commence through the collar of the whip stock' ina conventional manner, the whip stock wedging the drill bit olf the axisof the main bore as desired. To remove the whip stock, the drill pipestring is retracted until the upper ends of the flanges engage the lowerportions of the collar. At this time the drill pipe 11 may be rotateduntil the flanges register with the channel openings and the pipe thenraised further so that the flanges slide within the channel openings.This motion will continue until the ring 40 engages the underside of thecollar. The whip stock is then locked against relative rotation andswinging movements and the entire assembly may be removed from the borehole. vIt is not necessary that the lever elements re-engagetheshoulders in the collar flanges in order to remove the whip stocksince the annular ring flange 40 serves to lift the whip stock.

In the event it were desired to provide a device in which the leverelements could be re-extended to r'e-set the whip stock, the latch 38would be eliminated whereby a lessening of the mud pressure would resultin the compr'ession spring 33urging the piston member 29 upwardly. Thelever element 25 would then be free to be moved to its extended positionby the leaf spring 49. I

Various other modifications within the scope and spirit of the presentinvention will occur to those skilled in the art. The whip stock lockingand releasing apparatus is, therefore, not to be thought of as limitedto the particular structure shown for illustrative purposes.

What is claimed is:

1. A whip stock locking and releasing apparatus comprising, incombination: a collar on said whip stock having at least onelongitudinal channel formed in its inner wall; a shoulder portion insaid channel; a pipe section adapted to pass longitudinally through saidcollar; longitudinal flange means on said section receivable in saidchannel whereby said collar is held against rotation with respect tosaid section; a lever element positioned on said pipe section adjacentsaidflange means for swinging movement laterally away from said pipesection, the lower end of said lever' element engaging said shoulderwhen in a first position and free of' said shoulder when in a secondposition, said pipe section including a slot opening adjacent said leverelement; and means in said pipe section operable through said slotopening for moving said lever from said first to said second position.

2. A whip stock locking and releasing apparatus adapted to be insertedbetween a string of drill pipe and a drilling bit for holding said whipstock in a desired position while it is being lowered in a bore hole,comprising, in combination: a collar portion on said whip stock; a pipesection adapted to pass longitudinally through said collar portion;longitudinal channel means in said collar portion; longitudinal flangemeans on a given length of said pipe section receivable in said channelmeans whereby said collar portion is held against rotation with respectto said pipe section when said given length is in said collar portion; ashoulder in said channel; a lever element pivoted to said flange meansfor lateral swing-ing movement, the lower end of said lever beingadapted in a first position to seat on said shoulder, and in a secondposition to be free of said shoulder, a pipe section including a slotopening adjacent said lever element; and means operable through saidslot opening in said pipe section responsive to mud pressure for movingsaid lever element from said first to said second position whereby saidpipe section is free to move longitudinally through said collar portion.

3. A tool for holding a whip stock in a desired position andsubsequently releasing the whip stock, comprising: a collar portion onsaid whip stock; a pipe section adapted to axially pass through saidcollar portion; interengaging means on said pipe'section and collarportion for locking said section and portion against relative rotationalmovement while said portion surrounds said section; laterally movablelever means on said section for locking said section and portion againstrelative axial movement while said lever means is laterally extended,said pipe section including an opening to its interior adjacent saidlever means; and actuating means operable through said opening in saidpipe section for laterally retracting said lever means to free saidsection for axial movement through said collar portion therebydisengaging said interengaging means, whereby said section is free forboth rotational and axial movement.

1 4. A tool according to claim 3, in which said lever means includes alever element pivoted intermediate its ends to said interengaging meansfor arcuate movement in a vertical plane; a shoulder on said collarportion adapted to engaged by the lower end of said lever element whenin a first arcuate position and to be free of said end when in a secondarcuate position.

5. A tool according to claim 4, in which said actuating means includes:a piston member having a central mud passage, and a sloping side wallportion; said piston memher being vertically movable within said pipesection; the upper end of said lever element passing through said slotopening in said pipe section adjacent said sloping Side wall to engagethe same in camming relationship, whereby downward movement of saidpiston member cams said upper end of the lever element outwardly topivot said lever element from said first to said second position.

6. A tool according to claim 5, in which said pipe section is providedwith an undercut portion adjacent said -slot opening adapted to engage acorrespondingly contoured portion on said lever element adjacent itspivot point when said lever element is in its first position where bycompression forces are transmitted through said lever element to saidundercut portion to relieve said pivot point of said forces.

7. A tool according to claim 5, including biasing means normally holdingsaid piston in an up position and passage control means in said pistonmud passage whereby said piston is responsive to fluid pressure formoving the same downwardly.

8. A tool according to claim 7, including latch means adapted to engagesaid piston whenin its downward position to hold said piston in saidposition.

9. A tool according to claim 7 including a ball check valve positionedabove said piston and adapted to close off said mud passage duringinitial movement of said pis ton and to open said passage prior to finalpositioning of said piston to its downward position.

10. A tool according to claim 5, including axially spaced annular stopsadapted to engage annular portions of said piston member above and belowsaid slot opening respectively when said piston is in its downwardposition to provide fluid tight seals whereby mud is prevented frompassing through said slot opening to the interior of said pipe sectionabove and below said piston member.

11. A tool according to claim 10, including spring means normallybiasing said lever element to said first position.

12. A tool for holding a whip stock in a desired position andsubsequently releasing the whip stock, comprising: a collar portion onsaid whip stock; a pipe section adapted to axially pass through saidcollar portion; interengaging means on said pipe section and collarportion for locking said section and portion against relative rotationalmovement while said portion surrounds said section; laterally movablemeans on said section for locking said section and portion againstrelative axial movement while said movable means is laterally extended,said pipe section including a lateral opening through which a portion ofsaid laterally movable means extends; and actuating means operablethrough said lateral opening in said pipe section for laterallyretracting said movable means to free said section for axial movementthrough said collar portion thereby disengaging said interengagingmeans, whereby said section is free for both rotational and axialmovement.

References Cited in the file of this patent UNITED STATES PATENTS2,506,799 Livingston May 9, 1950 2,634,097 Zublin Apr. 7, 1953 2,766,010Hester Oct. 9, 1956

